I have a table view with a few cells. The text that fills up the cell is unpredictable (based on the result of an API request). What I want to do is adjust the cell's height based on if the cell's text is too lengthy for the cell (e.g. the cell adds '...' to the text).
That way whatever the result/text and gets presented into a table view cell is always fully shown.
I would prefer not to implement the heightForRowAtIndexPath because I would have to implement a lot of code to do so.
UPDATE:
When I say "I have a lot of code to do so", I mean I literally have a lot of code parsing out requests and checking for conditions and performing algorithms and plus I have many table views. Just moved that stuff to another method and Im off to go!
Could you point me to any resources demoing this, do you know how to do this?
You must implement heightForRowAtIndexPath to vary the height of your table rows, but there isn't necessarily alot of code needed to calculate the height.
Use NSString:sizeWithFont:constrainedToSize to calculate the cell size needed.
//szMaxCell contains the width of your table cell, and the maximum height you want to allow
// strCellContents is an NSString containing the text to display
CGSize szMaxCell = CGSizeMake (tableView.frame.size.width - 20,999);
UIFont *font = [UIFont systemFontOfSize:12]; // whatever font you're using to display
CGSize szCell = [strCellContents sizeWithFont:font constrainedToSize:szMaxCell lineBreakMode:UILineBreakModeWordWrap];
szCell contains the size of the label. You'll use this size both to calculate the frame of your UILabel in your cellForRowAtIndexPath, as well as in your heightForRowAtIndexPath.
Use heightForRowAtIndexPath. It shouldn't be lots of extra code. Just get a reference to the object you are populating your cell with, check out the length of that text value and return the height you need. That is exactly what that delegate method is designed for.
Related
How to design this table view cell..
Cell overlaps the another cell.
Please help me
Set the y offset of the pictureImageview to be negative i.e -50.0f or so, the image will appear as starting from the cell above.
I just tried AppleDelegate's solution but didn't work, because the top of every image is cut, maybe because it is beyond the cells bounds, even with clear color for background.
A different approach would be to believe that it's just a visual effect, and cells are not overlapping. This is possible by giving a different height for every cell with next code :
- (CGFloat)tableView : (UITableView *) tableView
heightForRowAtIndexPath : (NSIndexPath *) indexPath {
// RETURN A DIFFERENT HEIGHT FOR EVERY CELL DEPENDING ON INDEXPATH,
// INCREASING IT GRADUALLY.
}
In the next image, the black lines look like cells' top border, but maybe that's the effect, and the real limit is the red line :
Thinking this way, only the first cell requires a special treatment for the green titles.
Try setting constraints in storyboard and then keep the UIImageView's size/frame of image same when the image is set to UIImageView. Good Luck!
In my table cell I have long line of information and because of that I'm not able to show all the information properly. I tried to make the table cell's hight big but that didn't help.
below is the image of the table cell where you can not see the rest of the information.
Thanks
Mayur
You can take Custom cell and inside the same,take UILabel with the property of word wrap with Linebreakmode.Remember to take numberOfLines to 0. Hope that Helps you.
You Can Create a CustomCell inheriting UITableView class and set the size of the cell to the size of custom cell and to get multiple lines you can also set linebreakmode :
lblName.lineBreakMode = UILineBreakModeWordWrap;
lblName.numberOfLines = 2; //Specify Number Of Lines
My table view covers part of the view. If I have 20 objects, I am displaying all of them in a tableview. But I want to know that how many cell are loaded that are visible to the user.
(i.e. first 5 cells data is visible for me: when I scroll down, the remaining cells will load. Here I want to know without scrolling how many cell are loaded.)
Is this possible?
You can use [tableView visibleCells] count], which returns numbers of the table cells that are visible, if I understand correctly what you want.
The below code will give you the array of indexpath of cells currently visible
NSArray *visiblePaths = [self.tableView indexPathsForVisibleRows];
after getting the index path you can easily access the cell at a particular indexpath
Its usually : (tableView's height / cell row height ) + 1
Can you take the size of the visible part of the table, and then the size of one cell, and divide them to know how many of them fit in the screen?
Whenever I do:
xxx = [NSImage imageNamed:#"Package.png"];
xxx loads but it's width and height remain 0. And whenever I try loading it into an NSImageCell I get this error:
NSImageCell's object value must be an NSImage.
Can someone help me out? I've never had this problem before.
Edit: Sorry, I've missed this bit out. So when I do it in the data source delegate it does not work and it shows the above error after 'return cell;'.
NSImageCell* cell = [[NSImageCell alloc] init];
[cell setObjectValue:xxx]; // Using imageNamed doesn't help either
Edit 2: This is becoming aggravating. I don't understand what happened but the image loads height and width properly, but it still complains when I add it to an NSImageCell.
I see—so the table view aspect is relevant after all.
As the data source, your job is to return (and receive, in the case of user editing) the object values for the cells in the columns.
But you're not returning such a value; you're returning a cell. Thus, you're trying to set an image cell (created by the data source) as the value of an image cell (the existing one owned by the column).
The log message suggests that you have already set the column's cell as an image cell when you created the column, so all you need to do now is change your data source to always return the object value for the column, not a cell. For an image column, return the image. For a text column, return the string.
Note that NSTableView does not work like UITableView, where UITableViewCells are UIViews and you have as many cells as rows on the screen; in NSTableView, each NSTableColumn gets one and only one data cell, and that one cell is used to draw that column of every row. The cell draws its object value, which you provide to the cell, which you do by returning it (the object value) from your data source method.
The documentation about controls (an NSTableView is a kind of NSControl) and their cells is the Control and Cell Programming Guide.
My guess is it's returning nil, in which case getting the width/height will return 0.
Try:
xxx = [NSImage imageNamed:#"Package"]; // the extension is not needed on the desktop or iOS 4
and make sure the image is actually being copied into your application's Resources folder!
Having established that you are, in fact, receiving an NSImage instance (not nil) whose width and height are zero, the next step is to determine why that happens.
Can you open Package.png in Preview?
If so: What's its width and height in Preview's Info window? Does it have any resolution (DPI or pixels-per-meter) information? If so, what does that say?
If you crack open your application bundle, can you open that copy of Package.png in Preview?
When you log the description of the image, what's the output?
What's the output of logging the image's representations array? (This should be included in the image's own description, but I include it explicitly in case not.)
What happens if you delete your build folder and re-build?
I have an NSTableView that has 2 columns, one for an icon and the other for two lines of text. In the second column, the text column, I have some larger text that is for the name of an item. Then I have a new line and some smaller text that describes the state of the item.
When the name becomes so large that it doesn't fit on one line it wraps (or when you shrink the window down so small that it causes the names to not fit on a single line).
row1===============
| image | some name |
| image | idle |
row2================
| image | some name really long name | <- this gets wrapped pushing 'idle' out of the view
| image | idle |
===================
My question is, how could I keep the text from wrapping and just have the NSTableView display a horizontal scroll-bar once the name is too large to fit?
Scrolling in Cocoa is implemented with the NSScrollView which is a view instead of a cell so if you really want to implement horizontal scrolling for table view cells I think you'd have to subclass the whole NSTableView and implement the feature there. My suggestion (without knowing the specifics of your situation, of course) is that you don't do that, though, since it's nonstandard behaviour and would probably entail quite a bit of work.
Truncate Instead of Wrap
If you're using a standard NSTextFieldCell, just select "Truncates" for its layout value in IB instead of "Wraps".
If you have a custom NSCell where you're doing your own drawing (I assume this is the case here), you should create an NSParagraphStyle, set its line break mode, add it as a value for the NSParagraphStyleAttributeName key in the NSAttributedString's text attributes dictionary.
An example:
NSMutableParagraphStyle *paragraphStyle = [[[NSMutableParagraphStyle alloc] init] autorelease];
[paragraphStyle setLineBreakMode:NSLineBreakByTruncatingTail];
[attributedStr
addAttribute:NSParagraphStyleAttributeName
value:paragraphStyle
range:NSMakeRange(0,[attributedStr length])];
Cell Expansion Frames
If you don't want to wrap your lines of text in the table view cells, the standard method of allowing the user to see the whole text is to use cell expansion frames which are enabled by default:
Cell expansion can occur when the mouse hovers over the specified cell and the cell contents are unable to be fully displayed within the cell.
If they're not working for some reason and you're using a custom NSCell subclass, make sure you implement -drawWithExpansionFrame:inView: and -expansionFrameWithFrame:inView: in your cell. Also make sure you're not returning NO in your NSTableViewDelegate for -tableView:shouldShowCellExpansionForTableColumn:row: (if you have one).
Adjust Width of Whole Table View?
If what you want to do is to adjust the width of a specific column (and thus the whole table view, possibly causing the enclosing scroll view's horizontal scroll bar to appear) such that the text its cells contain would never be truncated or wrapped, you can probably do that in your NSTableViewDelegate, for example, by calling -cellSize for each row's cell in that column and resizing the column to the largest value (you'll want to only do this when the values change, of course).